U.S. patent number 7,280,665 [Application Number 10/506,782] was granted by the patent office on 2007-10-09 for image display device with built-in loudspeakers.
This patent grant is currently assigned to Sharp Kabushiki Kaisha. Invention is credited to Kohji Ohtsuka, Ichiro Tamura.
United States Patent |
7,280,665 |
Tamura , et al. |
October 9, 2007 |
Image display device with built-in loudspeakers
Abstract
An image display device has a main display body provided with a
thin display unit, a low-frequency loudspeaker (woofer) and two
middle and high frequency loudspeakers (tweeters) and a stand
supporting the main display body. The stand has a base being just
opposite at its top surface to a duct outlet of the woofer, thereby
sound emitted from the duct can be constantly absorbed by and
reflected from the base. A housing containing the first loudspeaker
and a pair of the second loudspeakers has a plurality of through
holes formed in a first area corresponding to an aperture of each
loudspeaker and a plurality of blind holes formed in a second area
surrounding the first area, wherein the second area for the first
loudspeaker is different in peripheral shape and/or size from the
second area for each of the second pair of loudspeakers.
Inventors: |
Tamura; Ichiro (Utsunomiya,
JP), Ohtsuka; Kohji (Kawachi-gun, JP) |
Assignee: |
Sharp Kabushiki Kaisha (Osaka,
JP)
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Family
ID: |
28035108 |
Appl.
No.: |
10/506,782 |
Filed: |
March 4, 2003 |
PCT
Filed: |
March 04, 2003 |
PCT No.: |
PCT/JP03/02527 |
371(c)(1),(2),(4) Date: |
September 07, 2004 |
PCT
Pub. No.: |
WO03/079718 |
PCT
Pub. Date: |
September 25, 2003 |
Prior Publication Data
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Document
Identifier |
Publication Date |
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US 20050129263 A1 |
Jun 16, 2005 |
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Foreign Application Priority Data
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Mar 15, 2002 [JP] |
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2002-071350 |
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Current U.S.
Class: |
381/333;
348/E5.13; 348/E5.133; 381/306; 381/388 |
Current CPC
Class: |
H04N
5/642 (20130101); H04R 1/26 (20130101); H04R
1/2857 (20130101); H04R 5/02 (20130101); H04N
5/66 (20130101); H04R 2499/15 (20130101) |
Current International
Class: |
H04R
25/00 (20060101) |
Field of
Search: |
;381/333,300-306,388,160,308,335,345,386,182,186,349,351,390-391,189
;181/144-145,147,199,155-156 ;361/681-683,686 ;348/836,838 |
References Cited
[Referenced By]
U.S. Patent Documents
Foreign Patent Documents
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801514 |
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Oct 1997 |
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EP |
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2239763 |
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Jul 1991 |
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GB |
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59-201600 |
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Nov 1984 |
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JP |
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3-147498 |
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Jun 1991 |
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JP |
|
7-274273 |
|
Oct 1995 |
|
JP |
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8-168037 |
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Jun 1996 |
|
JP |
|
09-284674 |
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Oct 1997 |
|
JP |
|
11-168783 |
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Jun 1999 |
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JP |
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11-259011 |
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Sep 1999 |
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JP |
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2001-42779 |
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Feb 2001 |
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JP |
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2001-145186 |
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May 2001 |
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JP |
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2002-152871 |
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May 2001 |
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JP |
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WO-01/50745 |
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Jul 2001 |
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WO |
|
Other References
Microfilm of the Specification and drawings annexed to the request
of Japanese Utility Model Application No. 177573/1980 (Laid-open
No. 100392/1982) (Tokyo Shibaura Electric Co., Ltd.). cited by
other .
CD-ROM of the Specification and drawings annexed to the request of
Japanese Utility Model Application No. 5196/1992 (Laid-open No.
65196/1993) (Mitsubishi Electric Corp.). cited by other .
Microfilm of the Specification and drawings annexed to the request
of Japanese Utility Model Application No. 44103/1990 (Laid-open No.
4493/1992) (Kenwood Corp.). cited by other.
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Primary Examiner: Le; Huyen
Attorney, Agent or Firm: Birch, Stewart, Kolasch &
Birch, LLP
Claims
The invention claimed is:
1. An image display device comprising: a main display body provided
with a display portion for presenting an image, a first loudspeaker
for reproducing sounds of low frequency, a second pair of
loudspeakers for reproducing sounds of middle and high frequencies,
and a duct for improving a low frequency sound property of the
first loudspeaker; and a stand for supporting the main display
body, wherein the stand has a portion being opposite to an outlet
of the duct.
2. The image display device as defined in claim 1, further
comprising a housing having the first loudspeaker and the second
pair of loudspeakers therein, the housing having a plurality of
through hole in a first area corresponding to an aperture size of
each loudspeaker and a plurality of blind holes in a second area
surrounding the first area, wherein the second area for the first
loudspeaker is different in peripheral shape and/or size from the
second area for each of the second pair of loudspeakers.
3. The image display device as defined in claim 2, wherein a ratio
of a total opening area of the through holes to the first area for
the first loudspeaker is larger than the ratio for the second pair
of loudspeakers.
4. The image display device as defined in claim 2, wherein an
aperture size of the first loudspeaker is larger than that of the
second loudspeakers.
5. The image display device as defined in claim 1, wherein an
aperture size of the first loudspeaker is larger than that of each
of the second loudspeakers.
6. The image display device as defined in claim 5, further
comprising a housing the first loudspeaker and the second pair of
loudspeakers therein, the housing having a plurality of through
holes in a first area corresponding to the aperture size of each
loudspeaker and a plurality of blind holes in a second area
surrounding the first area, wherein a ratio of a total opening area
of the through holes to the first area for the first loudspeaker is
lager than the ratio for the second pair of loudspeakers.
7. An image display device comprising: a main display body provided
with a display portion for presenting an image, and a housing
having a first loudspeaker for reproducing sounds of low frequency,
a second pair of loudspeakers for reproducing sounds of middle and
high frequencies, and a duct for improving a low frequency sound
property; and a stand for supporting the main display body, wherein
the housing has a plurality of through holes formed in a first area
corresponding to an aperture of each of the loudspeakers and a
plurality of blind holes formed in a second area surrounding the
first area, and the second area for the first loudspeaker is
different in peripheral shape and/or size from the second area for
each of the second pair of loudspeakers.
8. The image display device as defined in claim 7, wherein the
first and second loudspeakers are provided in the main display
body, with the first loudspeaker is mounted in a lower portion or
an upper portion of the main display body and each of the second
loudspeakers arranged respectively on left and right sides of first
loudspeaker.
9. The image display device as defined in 8, wherein an aperture of
the first loudspeaker is larger than that of each of the second
pair of loudspeakers.
10. The image display device as defined in 8, wherein a ratio of a
total opening area of the through holes to the first area for the
first loudspeaker is larger than the ratio for second pair of
loudspeakers.
11. The image display device as defined in claim 7, wherein the
first loudspeaker and the second pair of loudspeakers are mounted
on the stand with the first loudspeaker is placed at a center and
each of the second loudspeakers are arranged respectively on left
and right sides of the first loudspeaker.
12. The image display device as defined in 11, wherein an aperture
of the first loudspeaker is larger than that of each of the second
pair of loudspeakers.
13. The image display device as defined in 11, wherein a ratio of a
total opening area of the through holes to the first area for the
first loudspeaker is larger than the ratio for the second pair of
loudspeakers.
14. The image display device as defined in claim 7, wherein an
aperture of the first loudspeaker is larger than that of each of
the second pair of loudspeakers.
15. The image display device as defined in 14, wherein a ratio of a
total opening area of the through holes to the first area for the
first loudspeaker is larger than the ratio for the second pair of
loudspeakers.
16. The image display device as defined in claim 7, wherein a ratio
of a total opening area of the through holes to the first area for
the first loudspeaker is larger than the ratio for the second pair
of loudspeakers.
Description
FIELD OF THE INVENTION
The present invention relates generally to an image display device
and, more specifically, to a personal computer equipped with a thin
display such as a liquid crystal display (LCD) device and a plasma
display panel (PDP) device or an image display device applicable to
a display portion of a television receiver.
BACKGROUND OF THE INVENTION
In recent years, the production of small and thin electronic
devices has been advanced with development of electronic technology
and a growing consumers' demand for thinner and smaller home
electronic apparatuses. Indeed, various kinds of television
receivers are now available, which are constituted by using thin
CRTs, LCD panels and plasma-display panels. The television
receivers have video reproducing function and sound reproducing
function. The latter function is realized generally by means of
loudspeakers.
FIGS. 1 and 2 illustrate a typical exemplary structure of a
loudspeaker portion of a conventional television receiver (e.g.,
see the following Patent Document 1). FIG. 1(A) is a perspective
view of an essential portion of a television receiver in which a
loudspeaker box is mounted on an installing place. FIG. 1(B) is a
perspective view of a portion of a television receiver cabinet to
which a single loudspeaker unit is directly attached.
In FIG. 1(A), the television receiver 101 is composed mainly of a
front cabinet 102, a display (e.g., CRT) 103, and a rear cover 104.
A loudspeaker box 107 with a loudspeaker 106 mounted therein is
fitted to the front cabinet 102 via a vibration-proof material 108
with a machine screw 109. Sound generated from the loudspeaker 106
is output through a vent hole (not shown) mounted on the front
cabinet 102 and spread forward at the front face of the television
receiver 101.
In FIG. 1(B), a loudspeaker 106 is fixed to a front cabinet 102 of
a television receiver 101 via a vibration-proof material 108 with a
machine screw 109. Similarly, as described in the case of FIG.
1(A), sound generated from the loudspeaker 106 is output through a
vent hole (not shown) mounted on the front cabinet 102 and spread
forward at the front face of the television receiver 101.
FIG. 2 is a perspective view of another example of a conventional
television receiver. In the shown example, an L-shaped bent part of
a loudspeaker box 107 is placed between a display 103 and a rear
cover 104. Thus, the loudspeaker box can reproduce high quality
sound while realizing a thin profile of the television
receiver.
FIG. 3 is a plan view of another example of a conventional
television receiver wherein a pair of right and left loudspeakers
111 for reproducing sounds of relatively high frequency (in a range
of middle and high sound frequencies) are provided at a front face
of the television receiver 110 and a loudspeaker 112 for
reproducing sounds of relatively low frequency is provided at a
rear face of the television receiver 110, expanding a sound field
(e.g., see the following Patent Document 2). In this case, as
indicated in FIG. 3, the left and right sound signals of relatively
high frequency from the left and right loudspeakers travel along
corresponding paths D and directly reach a listener 120. Sound of
low frequency from the low frequency loudspeaker 112 reflects from
the rear wall 113 and the left and right walls 114, 115, travels
along the corresponding paths R and reaches the listener 120. The
remaining portion of sound from the same loudspeaker 112 diffracts,
travels along the left and right side walls 110a, 110b of the
television receiver 110 and reaches the listener 120. Thus, the
sound field is expanded sufficiently without increasing the lateral
width of the television receiver 110.
FIG. 4 illustrates another exemplary construction of a conventional
television receiver having a loudspeaker device composed of a
loudspeaker 138 with a sound introducing pipe 137 arranged on the
front face thereof and a woofer box 131 arranged on the rear face
thereof. The woofer box 131 has a downwardly directed port 140. The
television receiver has a cabinet 132 housing a CRT 134, a control
circuit board 135 and a loudspeaker device and a back cover 133.
The cabinet 132 has a sound emitting port 139 corresponding to the
sound guiding pipe 137 in the front side and an opening 136
corresponding to the port 140 in the underside so as to enhance the
effect of sound of low frequency (e.g., see the following Patent
Document 3).
Any television receiver is required to use a large loudspeaker
designed to reproduce sounds of relatively low frequency in
conjunction with two loudspeakers designed to reproduce sounds of
middle and high frequencies. On the other hand, recent television
receivers have a very restricted space allocated for loudspeakers
so as to achieve sophisticated design and appearance. For this
reason, a small-sized loudspeaker is necessarily applied as a
woofer. In other words, the appearance of the article has been
improved at the sacrifice of the quality of reproducible sound of
low frequency.
The conventional television receiver having a reduced lateral width
as shown in FIG. 1(A) has the following drawbacks. It has no space
for locating a loudspeaker box having a normal size and requires a
reduced profile of the loudspeaker box at the sacrifice of the
quality of reproducible sound. The conventional television receiver
as shown in FIG. 1(B) has the following drawbacks. Because of the
absence of a loudspeaker box, the television receiver has a small
dynamic range of its sound system and therefore cannot deliver high
quality sound reproduction. The conventional television receiver as
shown in FIG. 4 is a CRT type receiver whose design cannot be
applicable as a solution of improving the sound reproduction system
of wall-mounted television receivers using LCD panels.
In view of the above-described circumstances, the present invention
was made to provide an image display device which has a
high-fidelity sound-reproduction system composed of a loudspeaker
(woofer) for reproducing sounds of low frequency and two
loudspeakers (tweeters) for reproducing middle and high
frequencies, which is featured by the effect of expanded sound
field with improved external/internal design and is applicable in
particular to personal computers or television receivers equipped
with a thin display unit such as a LCD and PD panel.
Patent Document 1: Japanese Laid-Open Patent Publication No.
09-284674
Patent Document 2: Japanese Laid-Open Patent Publication No.
59-201600
Patent Document 3: Japanese Laid-Open Patent Publication No.
2001-145186
SUMMARY OF THE INVENTION
An object of the present invention is to provide an image display
device which comprises a main body for displaying video on a
display screen, a first loudspeaker for reproducing sounds of low
frequency, a second pair of loudspeakers for reproducing sounds of
middle and high frequency, a duct for improving the low-frequency
sound quality of the first loudspeaker and a stand for supporting
the display body, wherein the stand has a portion being opposite to
the duct outlet. A cabinet housing the first loudspeaker and the
second pair of loudspeakers has a plurality of through holes made
in a first area substantially corresponding to an aperture of each
loudspeaker and has a plurality of not-through (blind) holes within
the second area around the first area, wherein the periphery of the
second area for the first loudspeaker and the periphery of the
second areas for the second pair of loudspeakers are different from
each other in form and/or size. The above-described structure of
the loudspeaker system can obtain the stable quality of reproduced
sounds featured by the well-balanced reproduction of sounds of low,
middle and high frequencies by the effect that the sounds from the
first loudspeaker are absorbed by the bottom body of the stand and
reflected from the same, eliminating the possibility of decreasing
the sound quality by the affection of material of floor on which
the television receiver is mounted.
Another object of the present invention is to provide an image
display device which comprises a main body for displaying video on
a display screen, a first loudspeaker for reproducing sounds of low
frequency and a second pair of loudspeakers for reproducing sounds
of middle and high frequency range, wherein a box housing therein
the first and second loudspeakers has a plurality of through holes
made in a first area substantially corresponding to an aperture of
each of the loudspeakers and has a plurality of not-through (blind)
holes within the second area around the first area, wherein the
periphery of the second area for the first loudspeaker and the
periphery of the second area for the second pair of loudspeakers
are different from each other in form and/or size. The
above-described design can realize the loudspeaker system being
apparently larger than the actual size and attaining a
sophisticated appearance of the article. The first and second
loudspeakers arranged one on the both sides of the first
loudspeaker can present the visually symmetrical, fine external
design of the loudspeaker box while maintaining the mechanical
strength thereof.
Furthermore, the above-described image display device which may
mount in its main body the first loudspeaker and the second pair of
loudspeakers, wherein the first loudspeaker is arranged in the
lower or upper portion of the main body and the second pair of
loudspeakers are arranged one on the both sides of the first
loudspeaker.
Furthermore, the above-described image display device may have a
supporting stand on which the loudspeaker system is mounted in such
a manner that the first loudspeaker is located between the second
pair of loudspeakers. This can achieve a thinner design of a
television receiver owing to separate mounting of the loudspeaker
system on the stand.
Furthermore, the above-described image display device is featured
by the fact that the first loudspeaker has a larger aperture than
the second loudspeakers have.
Furthermore, the above-described image display device may have a
loudspeaker system featured by the fact that a ratio of a whole
area of through-holes relative to the first area for the first
loudspeaker is greater than a ratio of a whole area of
through-holes relative to the second loudspeakers.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a perspective view showing an exemplary construction of
an essential portion of a conventional television receiver.
FIG. 2 is a perspective view showing an exemplary construction of
an essential portion of a conventional television receiver.
FIG. 3 is a schematic plan view showing another exemplary
construction of a conventional television receiver.
FIG. 4 is a schematic cross-sectional view showing another
exemplary construction of a conventional television receiver.
FIG. 5 illustrates a television receiver according to an embodiment
of the present invention.
FIG. 6 is a schematic view of the inside of the main display unit
of the television receiver of FIG. 5 when viewing from the rear
face thereof.
FIG. 7 illustrates an inside construction view of a loudspeaker box
for reproducing sounds of relatively low frequency.
FIG. 8 is a perspective external view of a loudspeaker box for
reproducing sounds of relatively low frequency.
FIG. 9 is illustrative of an example of a loudspeaker system of a
television receiver according to the present invention.
FIG. 10 is illustrative of another example of a loudspeaker system
of a television receiver according to the present invention.
FIG. 11 is illustrative of another example of a loudspeaker system
of a television receiver according to the present invention.
FIG. 12 illustrates an exemplary arrangement of two loudspeakers
for reproducing sound of low frequency and for reproducing sounds
of middle and high frequencies in relation to main display device
according to the present invention.
FIG. 13 illustrates another exemplary arrangement of a loudspeaker
for reproducing sound of low frequency and a pair of loudspeakers
for reproducing sounds of middle and high frequencies in relation
to main display device according to the present invention.
FIG. 14 illustrates another exemplary arrangement of a loudspeaker
for reproducing sound of low frequency sounds and a pair of
loudspeakers for reproducing middle and high frequencies in
relation to main display device according to the present
invention.
FIG. 15 illustrates a television receiver according to a further
embodiment of the present invention.
PREFERRED EMBODIMENTS OF THE INVENTION
Preferred embodiments of the present invention will be described
below with reference to accompanying drawings.
FIG. 5 shows a television receiver according to an embodiment of
the present invention. FIG. 5(A) is a front view, FIG. 5(B) is a
right-side view and FIG. 5(C) is a rear view of the television
receiver. The television receiver 10 has a main display body 1
using a liquid crystal display (LCD) or a plasma display panel
(PDP) and the like as a thin display unit 2, wherein the main body
1 is further provided at its front lower portion with a pair of
left and right loudspeakers 4a, 4b for reproducing sounds of middle
and high frequencies and a loudspeaker (woofer) 3 for reproducing
sounds of low frequency placed between the pair of loudspeakers 4a
and 4b.
A stand 8 is composed of a support 5, a base 6 and a handle unit 7.
The stand 8 can be removably secured at its upper portion with
machine screws 9 to the rear surface of the main display body 1.
Thus, the main display body can be selectively used in any of two
ways: a stand type display (as supported by the stand on a floor)
or a wall type display (as being hung against the wall with the
stand removed). This offers a great convenience for use to the
user.
Referring to FIGS. 6 to 8, a loudspeaker (woofer) 3 for reproducing
sound of low frequency in the first embodiment of the present
invention as shown in FIG. 5 will be described below in detail.
FIG. 6 is a schematic view of the inside of the main display body 1
when it is viewed from the rear side. In FIG. 6, there are shown
loudspeakers 4a, 4b for reproducing sounds of middle and high
frequencies, a loudspeaker (woofer) box 11 for reproducing sound of
low frequency and a sound duct outlet (sound outlet) 12.
FIGS. 7 and 8 are views for explaining the internal construction of
the loudspeaker box 11 and the duct outlet 12 shown in FIG. 6. FIG.
7 shows an essential inside portion of the loudspeaker box 11 for
reproducing sound of low frequency. FIG. 8 is a perspective
external view of the loudspeaker box 11 for reproducing sound of
low frequency.
The low-frequency sound reproducing loudspeaker (woofer) box 11 is
featured by including a duct 13 having an elliptical profile. The
low frequency property of sound to be reproduced by the loudspeaker
box 11 may be improved by increasing the profile and length of the
duct 13. However, to decrease the depth of the main display body 1
of the television receiver, it is also necessary to reduce the size
and depth of the low-frequency sound reproducing loudspeaker box
11. For this purpose, the duct 13 of the woofer box 11 has an
elliptical section and is installed so that the short axis of its
section may be placed in the depth direction of the main display
body 1. The use of the duct 13 having a square section must be
avoided because it may cause the stagnation of sounds therein.
The duct 13 is arranged diagonally in the woofer box 11 so that it
may be as long as possible to improve the low-frequency sound
property. The duct 13 extends, bent downward and terminates in its
outlet 12 in the bottom of the television receiver.
The tip face 12a of the duct 13 in the outlet portion 12 is axially
tapered as show in FIG. 7 or the diameter of the outlet 12 may be
larger than that of the duct 13. The above-mentioned design of the
duct 13 can obtain the sufficient low-frequency sound property of
sounds to be reproduced by the woofer box having the reduced size
and profile.
When the television receiver 10 is supported by the stand 8 on a
floor, the sounds reproduced by the loudspeaker system may be
generally affected by material of the floor on which the receiver
is placed. For example, the sound may be easily absorbed by a
thick-carpeted floor or easily reflected by the metal-coated
floor.
The television receiver 10 according to the present invention
includes in the woofer box 11 the duct 13 having an outlet 12 being
open in the bottom of the main display body and the stand 8
supporting the main display body has a base surface 6 being just
opposite at its top surface to the duct outlet 12, thereby sound
output from the duct outlet 12 can be constantly absorbed by and
reflected from the base surface 6. Thus, the loudspeaker system can
stably reproduce high quality sound without being affected by the
flooring material. Referring to FIG. 9 to 11, an example of a
loudspeaker system of a television receiver according to the
present invention will be described below in detail. FIG. 9
illustrates an exemplary arrangement of three loudspeakers in the
television receiver. FIG. 9(A) is a partially enlarged view of an
exemplary housing (cabinet, etc.) incorporating three loudspeakers
3 (for reproducing low-frequency sound), 4a and 4b (for reproducing
sounds of middle and high frequencies). FIG. 9(B) is a section
taken along line B-B in FIG. 9(A).
Similarly, FIGS. 10 and 11 show another exemplary arrangement of
three loudspeakers in the television receiver. FIG. 10A (11A) is a
partially enlarged view of a housing incorporating three
loudspeakers. FIG. 10B (11B) is a sectional view taken along line
B-B in FIG. 10A (11A)
In a main display body 1 of a television receiver 10 provided with
a thin display unit, a loudspeaker 3 for reproducing sounds of low
frequencies and two loudspeakers 4a, 4b for reproducing sounds of
middle and high frequencies are attached to the inside of a cabinet
20 composing a housing of the main display body 1. Sounds
reproduced by these loudspeakers are output from the inside to the
outside of the cabinet 20.
In each of the examples shown in FIGS. 9 to 11, each of the
speakers 3, 4a and 4b is attached to the inside wall of the cabinet
20 which has a plurality of through holes 21 made in a wall area R1
corresponding to an aperture of each of the loudspeakers attached
thereto. In other words, outer diameter of the wall area R1 is
substantially equal to the aperture of each of the loudspeakers.
The cabinet 20 has a plurality of not-through holes (blind holes)
22 made on an area R2 surrounding the area R1. The blind holes 22
are formed on the external surface of the cabinet 20, i.e., they
are viewable to the user from the outside of the cabinet 20.
The through holes 21 and the blind holes 22 are each of about 0.5
to 2 mm in diameter and made in the quantity of several tens to
several thousands per area for each loudspeaker. The area R2 having
blind holes 22 formed therein for the loudspeaker 3 for reproducing
sound of low frequency is different in size from the area R2 having
blind holes 22 formed therein for each of the loudspeakers 4a, 4b
for reproducing sounds of middle and high frequencies. In other
words, the peripheral form and/or size of the area R2 for the
loudspeaker 3 is different from that of the area R2 for each of the
loudspeakers 4a and 4b.
Since the cabinet 20 is provided with area R2 with blind holes 22
formed therein around the area R1 having through holes 21 made
therein as described above, each of the loudspeakers can be viewed
apparently larger than its actual size, realizing a sophisticated
appearance of the cabinet 20. The symmetrical arrangement of the
loudspeakers 4a and 4b placed one on both sides of the loudspeaker
3 presents the well-balanced design of the loudspeaker cabinet 20
with an excellent external appearance while maintaining the
sufficient mechanical strength of the cabinet 20.
For example, with the loudspeaker cabinet 20 designed in such that
the aperture of the loudspeaker 3 for reproducing sound of low
frequency is larger than the aperture of the loudspeaker 4a or 4b
for reproducing sounds of middle and high frequencies while the
area R2 with blind holes 22 formed therein for the low-frequency
sound reproducing loudspeaker 3 is smaller than the area R2 with
blind holes 22 formed therein for each of the middle and high
frequency sound reproducing loudspeakers 4a and 4b, the user may
visually recognize the loudspeaker 3 is small in comparison with
the loudspeakers 4a and 4b and have a favorable impression of the
sound effect owing to more sufficient low-frequency sound output
from the loudspeaker 3 than the balance between the low-frequency
sound and the middle and high frequency sounds visually obtained.
In addition, the cabinet 20 has through holes only in the areas R1
corresponding to the respective loudspeakers' apertures and blind
holes in other areas R2 not to allow dust into the inside of the
cabinet and to prevent the occurrence of trembling sound. The
absence of unnecessary openings in the cabinet 20 minimizes the
leakage of sounds, maintaining the baffling effect of the cabinet
20.
A ratio of a total opening area of through holes 21 to a total area
of a portion R1 (area R1) of the cabinet 20 is defined as an
opening ratio. In the construction of the loudspeaker system shown
in FIG. 9, the middle and high frequency sound reproducing
loudspeakers 4a and 4b and the low-frequency sound reproducing
loudspeaker 3 have the same aperture but the opening ratio of the
through holes 21 for the loudspeaker 3 is different from that of
the through holes 21 for each of the loudspeakers 4a and 4b. In the
shown case, the opening ratio of through holes 21 for the
loudspeaker 3 is larger than that for each of the loudspeakers 4a
and 4b, thereby the low-frequency sound property is improved,
attaining an improved balance between the low-frequency sound and
middle and high frequency sounds.
In-the construction shown in FIG. 9, the blind-hole-formed areas R2
for the low-frequency sound loudspeaker 3 and the middle and high
sound loudspeakers 4a and 4b have the same round shape at their
peripheries.
In the construction of the loudspeaker system shown in FIG. 10,
similarly with the example of FIG. 9, the middle and high frequency
sound reproducing loudspeakers 4a and 4b and the low-frequency
sound reproducing loudspeaker 3 have the same aperture sizes but
the opening ratio of the through holes 21 for the loudspeaker 3 is
different from that of the through holes 21 for each of the
loudspeakers 4a and 4b. In the shown case, the opening ratio for
the loudspeaker 3 is larger than that for each of the loudspeakers
4a and 4b, thereby the low-frequency sound property is improved,
attaining an improved balance between the low-frequency sound and
middle and high frequency sounds.
In different from the construction shown in FIG. 9, the loudspeaker
system of FIG. 10 is featured by the design that the
blind-hole-formed areas R2 for the low-frequency sound loudspeaker
3 and the middle and high sound loudspeakers 4a and 4b have the
same square-shaped peripheries.
The constructions of the speaker systems as shown in FIGS. 9 and 10
can enhance the low-frequency sound and show the speakers to be
larger than its actual size, realizing the sophisticated appearance
of the system. The areas R1 each including a plurality of through
holes 21 made therein have peripheries substantially similar in
shape to those of corresponding loudspeakers 3, 4a and 4b while the
areas R2 with blind holes 22 formed therein for respective
loudspeakers may have any shape of their peripheries such as, for
example, round, oval, quadrangular and polygonal. The maximum size
of the areas R2 may be determined based on the mechanical strength
of the cabinet 20 and the relation with the thin display unit 2 and
the like. The sizes of the blind-hole-formed areas R2 may be
determined irrespective of the sizes of the corresponding areas R1
having the through holes 21 formed therein. For example, the area
R2 having the blind holes 22 formed therein for any loudspeaker may
be of a small size even when the loudspeaker has a large
diameter.
In the construction of the loudspeaker system shown in FIG. 11, the
low-frequency sound loudspeaker 3 is larger in aperture size than
the middle and high frequency sound loudspeakers 4a and 4b and the
blind-hole-formed area R2 for the loudspeaker 3 is different in
shape of its periphery from the blind-hole-formed areas R2 for the
loudspeakers 4a and 4b. In the shown instance, the areas R2 with
blind holes 22 formed therein for the middle and high frequency
sound reproducing loudspeakers 4a and 4b have a round shape at
their peripheries while the area R2 with blind holes 22 formed
therein for the low-frequency sound reproducing loudspeaker 3 has a
quadrangular shape at its periphery.
The above-described embodiment can enhance the low-frequency sound
and show the speaker to be larger than its actual size, obtaining
the sophisticated appearance of the system. The areas R1 each
including a plurality of through holes 21 made therein have
peripheries substantially similar in shape to those of
corresponding loudspeakers 3, 4a and 4b while the areas R2 with
blind holes 22 formed therein for respective loudspeakers may have
any shape of their peripheries such as, for example, round, oval,
quadrangular and polygonal. The maximum size of the
blind-hole-formed areas R2 may be determined based on the
mechanical strength of the cabinet 20 and/or the relation with the
thin display unit 2 and the like. The sizes of the
blind-hole-formed areas R2 may be determined irrespective of the
sizes of the corresponding areas R1 having the through holes 21
formed therein. For example, the area R2 having the blind holes 22
formed therein for any loudspeaker may be of a small size even when
the loudspeaker has a large aperture.
FIGS. 12 to 14 show other respective embodiments which are featured
by different arrangements of the loudspeaker 3 for reproducing
low-frequency sound and the pair of loudspeakers 4a and 4b for
reproducing the middle high sounds. In the embodiment shown in FIG.
12, a pair of loudspeakers 4a and 4b for reproducing sounds of
middle and high frequencies are arranged one on the left and right
sides on the front upper part of a thin display unit 2 of a main
display body 1 and a loudspeaker (woofer) 3 for reproducing sounds
of low frequency is arranged at the center between the loudspeakers
4a and 4b on the front upper part of the thin display unit.
In the embodiment shown in FIG. 13, a pair of loudspeakers 4a and
4b for reproducing sounds of middle and high frequencies are
arranged one on the front left and right sides of a thin display
unit 2 of a main display body 1 and a loudspeaker (woofer) 3 for
reproducing sounds of low frequency is arranged on the front lower
part of the thin display unit 2.
In the embodiment shown in FIG. 14, a pair of loudspeakers 4a and
4b for reproducing sounds of middle and high frequencies are
arranged one on the front left and right sides of a thin display
unit 2 of a main display body 1 and a loudspeaker (woofer) 3 for
reproducing sounds of low frequencies is arranged on the front
upper part of the thin display unit 2.
In each of the embodiments of FIGS. 12 to 14, the above described
through holes 21 and blind holes 22 are formed in the way described
in FIGS. 9 to 11 to attain the same effect as described above.
FIG. 15 shows a television receiver according to a further
embodiment of the present invention. FIG. 15(A) is a front view,
FIG. 15(B) is a right side view and FIG. 15(C) is a rear view of
the television receiver. The television receiver 10 has a main
display body 1 using a liquid crystal display (LCD) or a plasma
display panel (PDP) and the like as a thin display unit 2 and can
be supported by a stand 8 composed of a support 5, a base 6 and a
handle 7. The stand 8 can be removably attached at its upper
portion with machine screws 9 to the rear surface of the main
display body 1. Thus, the main display body can be selectively used
in any of two ways: a standing type display (as supported by the
stand on a floor) or a wall type display (as being hung against the
wall with the stand removed). This offers a great convenience for
use of it by the user.
The stand 8 is provided at its base 6 with a low frequency sound
reproducing loudspeaker (woofer) 3 arranged at a center thereof and
two middle and high frequency sound reproducing loudspeakers 4a and
4b arranged left and right sides thereof.
In this instance, a thin and compact television receiver is
realized since the loudspeaker system is separately mounted on the
stand base.
In this embodiment, a low-frequency sound reproducing speaker
(woofer) box 11 as shown in FIGS. 6 to 8 is mounted in such a way
that an outlet 12 of a duct 13 is placed in outward direction. In
the present embodiment, the outlet 12 of the duct 13 is placed
behind the stand support 5.
Although the loudspeakers 3, 4a and 4b are mounted on the base 6 of
the stand 8, any one or all of them may be mounted on the support 5
of the stand 8.
In the embodiment, through holes 21 and blind holes 22 are formed
in the way described in FIG. 15 to attain the same effect as
described before with reference to FIGS. 9 to 11.
As is apparent from the foregoing, the television receiver 10
according to an aspect of the present invention includes in the
woofer box 11 the duct 13 having an outlet 12 open in the bottom of
the main display body and the stand 8 supporting the main display
body has a base 6 being just opposite at its top surface to the
duct outlet 12, thereby sound output from the duct outlet 12 can be
constantly absorbed by and reflected from the base surface 6. Thus,
the loudspeaker system can stably reproduce well-balanced
high-quality sounds with no affection of the floor material,
preventing the occurrence of a tremble.
The cabinet 20 of the main display body 1 or the housing having
each loudspeaker of 3, 4a, and 4b of such as the base 6 therein is
provided with a plurality of through holes 21 formed in areas R1
substantially corresponding to apertures of respective loudspeakers
and a plurality of blind holes 22 formed in areas R2 surrounding
the respective areas R1. This makes the loudspeakers look larger
than actual, attaining a sophisticated appearance. The symmetrical
arrangement of the middle and high frequency sound reproducing
loudspeakers 4a and 4b on the both sides of the low-frequency sound
reproducing loudspeaker 3 in the cabinet 20 or the stand base 6
presents a well-balanced, good-designed appearance of the
loudspeaker system while maintaining the necessary mechanical
strength of the cabinet 20 and the like.
Furthermore, the cabinet 20 has through holes only within the areas
R2 corresponding to aperture sizes of corresponding loudspeakers
and blind holes in other areas R1 not to allow dust into the inside
of the cabinet 20 and to prevent the occurrence of a tremble. The
absence of unnecessary openings in the cabinet 20 minimizes the
leakage of sounds, maintaining the baffling effect of the cabinet
20.
The television receiver according to the present invention is
designed to be selectively used in any of two ways: a television
receiver secured to a stand to be placed on a table or a floor or a
wall television receiver to be hung against a wall without using a
stand 8 which can be removed from the main display body. Thus, a
convenient flat television receiver can be provided.
A further flat and compact television receiver can be provided by
mounting three loudspeakers 3, 4a and 4b on the stand 8 (on the
base 6 or the support 5 of the stand).
The loudspeaker housing (cabinet 20) of the television receiver has
a plurality of through holes in each of areas R1 having sizes
corresponding to aperture sizes of respective loudspeakers 3, 4a
and 4b and the opening ratio of the through holes 21 for the
loudspeaker 3 is larger than that of the through holes 21 for each
of the loudspeakers 4a and 4b, thereby the low-frequency sound
property is improved attaining an improved balance between the low
frequency sound and middle and high frequency sounds.
INDUSTRIAL APPLICABILITY
The image display device according to the present invention can be
applied to a personal computer or a television receiver provided
with a thin display unit such as a liquid crystal display (LCD),
plasma display panel (PDP) and the like. It has a high quality
loudspeaker system which is featured by an improved sound field
expanding effect by using a low frequency sound reproducing
loudspeaker (woofer) and a pair of middle and high frequency sound
reproducing loudspeakers (tweeters).
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